Grating



Patented Mar. 11, 1930 PATENT OFFICE PETER EMIL FELTES, OF KANSAS CITY, MISSOURI GBATING Application filed June 4, 1928. Serial No. 282,564,

My invention relates to gratings and more particularly to reinforced structures comprising support bars secured together by transverse tie bars, the principal objects of the invention being to minimize the amount of material necessary for constructing a grating, to provide a high degree of initial rigidity in a grating, to lock the tie bars with the support bars by means integral with the tie bars 1 and to enhance resistance to stresses in a grating in a plurality of directions. Further objects of the invention are to provide a method of constructing grating whereby the support bars may be arranged in permanent relation before connecting members are attached, the tie bars and support bars may be twisted after association with the support bars to produce shoulderlike portions for spacing and locking the support bars in predetermined relation.

In accomplishing these and other objects of the invention I have provided improveddetails of structure, the preferred forms of V which are illustrated in the accompanying drawings, wherein:

Fig. 1 is a perspective view of a portion of a grating representing a method of constructing the same according to my invention.

Fig. 2 is a sectional view illustrating the {)elation between a'tie bar and the support ars.

Fig. 3 is an elevational view of a portion of a support bar illustrating two tie bars insection.' I

Fig. 4 is a fragmentary plan view of support bars and a tie bar connecting the same.

Fig. 5 illustrates a modified form of grating for supporting metal lath.

Referring in detail to the drawings:

A portion of a grating generally designated 1 isillustrated as comprising spaced support bars, such as 2 and 3, the bar 3 being a marginal or rim support bar comprising one side of the grating, and tie bars 4 extending in slots 5 in the support bars. In the embodiment of the invention shown in Figs. 1 to 4, the support bars are flat and adapted for positioning on their edges 6, the opposite edges 7 providing the tread surface when the structure is used for closing a floor opening, or for a stair tread, or the like. The tie bars are also initially flat, and the slots are adapted to receive them snugly, the outer ends of the bars being peened over the outer face of the rim bar 3 to provide retaining heads 8 for engaging the tie bar ends with the rim bar.

I provide a special method for producing the gratings herein illustrated, whereby the flat portion 9 (Fig. 1) of a fiat tie bar that lies between adjacent support bars is distorted to provide shoulder-like integral wings 10 and 11 extending oppositely from the axis of the tie bar for spacing the support bars and looking the same in spaced relation. A wrench 12 55 having jaws 13 adapted to fit closely over the flat portion 9 of a tie bar is inserted between the support bars and engaged with such flat portion 9, and rotated to twist the tie bar portion, whereby upper and lower support bar-engaging shoulders 14 and 15 are produced on each side of the wrench, and at each end of the wings, the upper shoulders 14 comprising portions of the upwardly-extending wing 10 and the lower shoulders 15 comprising portions of the oppositely extending wing 11.

The wings, and the shoulders, are integral with the plane portion 16 of the tie bar that is restrained from distortion by snug egngagem'ent in the slots of adjacent support ars.

The slots may be suitably spaced from the edges of the support bars for any particular purpose, for example, as in Figs. 1 to 4, for distorting the portions between support bars to right-angular relation with the slot-retained portions 16, and for causing edges 17 of the wings to lie substantially in the plane 0 of the tread edges of the support bars, as particularly illustrated in Fig. 2.

The staggered relation of the sets of aligned slots provides therefore that alternate sets of slots may lie adjacent the upper and lower surfaces of the grating, respectively, and that the tie bars positioned in the lower slots will be twisted to position the edges 18 of the downwardly extending wings substantially in the plane of the lower surface of the grating, the resulting staggered relation of the reenforcing tie bar wings being clearly disclosed in Fig. 3.

The width and shape of the wrench jaws, and the extent of twisting of the tie bar portions may be varied to suit particular conditions, but I prefer to provide support bars and tie bars adapted for twisting of the tie bar portions beyond the limit of natural elasticity of the metal to confer the final set of the metal, but within the tensional limit to avoid fracture and shearing.

To facilitate the assembly of grating parts and twisting of the tie-bars, the support bars are supported in a jig or frame 19 in the spaced relation which they are to occupy in the completed grating, the frame having slots to receive the support bars to retain the support bars for receiving the tie bars and for twisting of the tie bars. The support bars may extend in any desired angular relation with each other to provide a grating having desired spacings of adjacent ends of support bars, the bars being parallel in the illustrated usage. A relatively small and constant proportion of the initial length of a tie bar is absorbed in the twisting operation, so that the required length of a tie bar for a particular grating may be predetermined.

A grating constructed by my improved method and having the structural features described, will have a high degree of initial rigidity due to the twisting of the tie bars whereby the normal flexibility of the tie bars is largely exhausted. The tie bars serve as trusses, and the close engagement of integral portions of the tie bars with opposite sides of the support bars and with adjacent support bars, cause distribution of any concentrated load over a relatively large area of the grating. The truss-like effect is enhanced by the staggered relation of adjacent tie bars. The integral wings and shoulders of the tie bars maintain the support bars in Vertical position to sustain their maximum load.

The structure may be modified for application to other situations, by suitable provision of slots and tie bars, twisting of the tie bars to produce wings having desired relation with the support bars, and by adapting support bars to a particular service, one such modification adapted for supporting metal lath is illustrated in Fig. 5. In this form a support bar 2 comprises a wall member having its opposite edges 6 and 7 extending vertically and provided with slits 21 leading to sockets 22 to receive portions 23 of metal lath 24 for attaching the latch to the grating. The forming of the slits and sockets produces clamping fingers 25 which may be moved away from the bars to facilitate admission of the latch portions, and the fingers may be rebent to engage the bars and close the recesses and stake the portions 23 therein.

What I claim and desire to secure by Letters Patent is:

1. In a grating spaced support bars provided with sets of aligning longitudinal slots, the sets being in staggered relation, and tie bars positioned in aligned slots having integral portions extending oppositely from the axes of the tie bars.

2. In a grating, spaced support bars provided with sets of aligning longitudinal slots, the sets being in staggered relation, and tie bars positioned in aligned slots having integral portions extending diversely over the inner face of each support bar.

3. In a grating, spaced support bars having staggered sets of aligned longitudinal slots adjacent the upper and lower edges of the bars respectively, and a tie bar having less Width than the support bars mounted in aligned slots and having portions between adjacent bars twisted to position an edge of said portion substantially in the plane of adjacent edges of the support bars.

In testimony whereof I affix my signature.

PETER EMIL FELTES. 

